gbvona
Member
The short version of the story is that my 1970 NADA P6 suffered a carb swap (to HIF6's) and when I got the car the accelerator linkage was a total bodge. The BW35 tranny cable was not even connected.
I have made efforts to rationalize the carb linkage, which required fabricating a crank arm from the accelerator rod (that rotates when you press the pedal) to the carburetters. I guessed at the length of said crank and have apparently guessed wrong. The crank on the rod for the tranny cable is the original bit and I am using the original manifold casting.
Clearly there must be some coordination between the opening of the throttle and the distance of pull on the tranny cable. At present I have it set so that the tranny cable (which closes the pressure valve at idle) starts to pull out when the engine just gets off of idle.
Even so, the tranny tends to hang in lower gear too long and shifts abruptly. (Note that I have thoroughly cleaned the tranny, replaced the wear parts and adjusted the adjustments as per the shop manual, and am using the correct juice). To my thinking the pressure is too high at a given level of throttle.
I need to make a new crank arm for the carbs that reduces the pull on the tranny cable (giving a lower pressure) for a given throttle opening. It would help immensely if someone could make a measurement of how far the tranny cable is pulled out (from idle) with the throttle wide open (WOT). This would at least give me a ballpark estimate of the relationship between the length of the two arms (the tranny arm and the throttle arm), in that I could fabricate a carb arm that would match WOT with this distance of pull on the tranny cable.
As always, thanks for your advice!
gbvona
I have made efforts to rationalize the carb linkage, which required fabricating a crank arm from the accelerator rod (that rotates when you press the pedal) to the carburetters. I guessed at the length of said crank and have apparently guessed wrong. The crank on the rod for the tranny cable is the original bit and I am using the original manifold casting.
Clearly there must be some coordination between the opening of the throttle and the distance of pull on the tranny cable. At present I have it set so that the tranny cable (which closes the pressure valve at idle) starts to pull out when the engine just gets off of idle.
Even so, the tranny tends to hang in lower gear too long and shifts abruptly. (Note that I have thoroughly cleaned the tranny, replaced the wear parts and adjusted the adjustments as per the shop manual, and am using the correct juice). To my thinking the pressure is too high at a given level of throttle.
I need to make a new crank arm for the carbs that reduces the pull on the tranny cable (giving a lower pressure) for a given throttle opening. It would help immensely if someone could make a measurement of how far the tranny cable is pulled out (from idle) with the throttle wide open (WOT). This would at least give me a ballpark estimate of the relationship between the length of the two arms (the tranny arm and the throttle arm), in that I could fabricate a carb arm that would match WOT with this distance of pull on the tranny cable.
As always, thanks for your advice!
gbvona